function updateClock() {
      const now = new Date();
      const hours = String(now.getHours()).padStart(2, '0');
      const minutes = String(now.getMinutes()).padStart(2, '0');
      const seconds = String(now.getSeconds()).padStart(2, '0');
      document.getElementById('clock').textContent = `${hours}:${minutes}:${seconds}`;
    }
    setInterval(updateClock, 1000);
    updateClock(); // 初始化时钟显示